Regional Citrate Anticoagulation for Intermittent Hemodialysis in Dogs

Abstract

BackgroundThe traditional systemic heparinization used for anticoagulation in extracorporeal therapies may cause fatal complications in animals at risk of bleeding.Hypothesis/ObjectivesTo develop and validate a protocol of regional citrate anticoagulation (RCA) for intermittent hemodialysis in dogs.AnimalsA total of 172 dogs treated with hemodialysis for acute kidney injury.MethodsIn vitro titration was performed, adding trisodium citrate and calcium chloride to heparinized canine blood. A tentative protocol was used first in 66 treatments with additional heparinization and subsequently in 518 heparin‐free treatments. Safety and adequacy of RCA were assessed based on clinical and laboratory monitoring, dialyzer pressure gradient, treatment completion, and visual scoring of the extracorporeal circuit.ResultsAddition of 1 mmol/L citrate to heparinized blood decreased the ionized calcium concentration by 0.23 mmol/L (95% confidence interval [CI], 0.16–0.30) and 1 mmol/L calcium increased it by 0.62 mmol/L (95% CI, 0.45–0.79). Heparin‐free treatments were initiated with infusion of trisodium citrate (102 mmol/L) at 2.55 mmol/L blood and calcium chloride (340 mmol/L) at 0.85 mmol/L. Citrate and calcium administrations were adjusted in 27 and 34% of the treatments, respectively. Overall, anticoagulation was satisfactory in 92% of the treatments, with expected azotemia reduction in 95% (urea) and 86% (creatinine), stable dialyzer pressure gradient in 82%, and clean extracorporeal circuits in 92% of the treatments. Eighteen treatments (3.5%) were discontinued prematurely, 9 because of clotting and 9 for reasons unrelated to the RCA procedure.Conclusions and Clinical ImportanceRegional citrate anticoagulation allows safe and efficient heparin‐free hemodialysis in dogs at risk of bleeding.

Treatment of a flunixin meglumine overdose with intravenous administration of lipid emulsion and therapeutic plasma exchange in a Nigerian dwarf buck kid (Capra aegagrus hircus)

“…Other anticoagulation strategies such as regional citrate anticoagulation (RCA) limited to the blood in the extracorporeal circuit could have been attempted to overcome the goat's hypercoagulability. However, a safe and efficient RCA protocol is currently only developed in dogs in veterinary medicine 23 …”

Acute kidney injury management using intermittent low efficiency haemodiafiltration in a critical care unit: 39 dogs (2012–2015)

“…As an integral part of our standardization process, anticoagulation is delivered through a fixed protocol with minimal heparinizing. While different methods to provide anticoagulation during RRT has been published [23, 34], the one described in the present study appeared to be close to heparin-free dialysis protocol previous published [35, 36]. Considering the use of dialysis membranes coated with anti-coagulants, such as heparin-binding to surface-treated AN69, and high probability of coagulopathy in a high number of our dogs, our no to low anti-coagulation protocol tally with actual recommendations [5, 23, 35].…”

“…Despite the number of coagulation events, only few (6.9%) were severe enough to require a filter change-out. To decrease clotting events, and at the cost of increased complexity, adaptation to the protocol may be considered, as increasing pre-filter replacement fluid rate (to dilute blood before reaching the filter), the use of continuous heparin administration, or citrate anticoagulation [34].…”

Acute kidney injury due toLeptospira interrogansin 4 foals and use of renal replacement therapy with intermittent hemodiafiltration in 1 foal

“…Dialysis was performed using a Gambro AK 200 R Ultra S machine with a Fresenius FX 80 filter and Gambro BL200BD blood tubing with total extracorporeal volume of 241 mL. Bicarbonate‐based dialysate (A341G, Dr G. Bichsel Laboratory, Interlaken, CH; and BiCart R , Gambro Lundia AB, Sweden) was used, and heparin‐free regional citrate anticoagulation was performed, adapted from a protocol used for intermittent hemodialysis in dogs, using trisodium citrate (Trisodium citrate 30 g/L, 102 mmol/L, Dr G. Bichsel Laboratory; initial rate of 2.5 mmol/L blood or 4.6 μmol/kg/min at the chosen blood flow rate) and calcium chloride (Calcium chloride 50 g/L, 340 mmol/L, Dr G. Bichsel Laboratory; initial rate of 0.85 mmol/L blood or 1.6 μmol/kg/min at the chosen blood flow rate) as citrate and calcium sources, respectively . The dialysis prescription was designed to provide a urea clearance of approximately 1.5 mL/kg/min for 4 hours, corresponding to a blood flow rate of 200 mL/min.…”